1. Field of the Invention
The invention relates to eye charts, and method for using the eye chart for correcting certain visual deficiencies. More particularly, the invention relates to a new and different eye chart and method of using it to correct for amblyopia and diplopia.
2. Description of the Related Art
There have been many eye charts designed for testing visual acuity. Some charts incorporate various characters or figures printed on a contrasting background. Others incorporate opaque figures printed on a transparency for projection onto a screen. U.S. Pat. Nos. 2,385,992; 3,011,394; and 4,257,690 disclose examples of various kinds of eye testing charts that have been available up to now.
A feature common to previously known charts is that they are designed only to test the condition of the eyes. None are designed for treating existing visual deficiencies.
Amblyopia is a condition in which the eyes see with differing degrees of clarity or sharpness. The better eye tends to do all the work while the weak eye does little or none. The weak eye may also wander. Diplopia is a condition in which a person sees double images when viewing small pictures or fine print, such as newspaper print. This is due to unequal action of the eye muscles. People who write or draw extensively may develop this problem because the hand which is writing or drawing blocks the work from the view of the corresponding eye. The eye whose view is blocked is not used, and the muscles become weak.
To overcome and correct these conditions, it is important for an individual to develop greater control over the eye muscles. Consequently, it would be desirable to have a simple, yet effective means and method for exercising the eyes and the muscles associated with the eyes, to help overcome amblyopia and diplopia.
The eye chart and method in accordance with the present invention may be advantageously used to rehabilitate the vision of a person suffering from certain conditions, such as amblyopia or diplopia. Use of the inventive chart in accordance with the described methods increases muscular strength and improves control of the muscles associated with the eye. A chart in accordance with the present invention is very inexpensive, and the inventive method may easily be practiced by a lone individual, without additional aid or equipment. An optometrist can use the chart in conjunction with other equipment to treat eye muscle problems.
It is an object of the present invention to provide means for aiding in the treatment of certain visual impairments.
It is an object of this invention to provide means to treat amblyopia and diplopia.
It is another object of this invention to provide a method for helping to correct certain temporary eye problems.
It is an object of this invention to provide a method which can be easily practiced by an individual without the aid of others and without complex or expensive equipment.